foodconsumer.org: Obesity may raise kidney stone risk

Obesity may raise kidney stone risk
================================================================================
admin on 02/18/2010 12:40:00
 
Obesity may double the risk of developing kidney stones regardless of its
severity, according to a new study in the Feb 2010 issue of Journal of Urology.
"The common thinking was that as weight rises, kidney stone risk rises as well,
but our study refutes that," said lead author Brian R. Matlaga at the Johns
Hopkins University School of Medicine. "Whether someone is mildly obese or
morbidly obese, the risk for getting kidney stones is the same."
Numerous epidemiological studies in the last decade have pointed to the
possibility that being obese may raise the risk for kidney stone disease.
The current study was meant to examine whether the severity of obesity makes any
difference in the risk of kidney stone disease.
The researchers analysed data from a national insurance claims database which
had health records for 95,598 people who had completed a health risk assessment
form with information on their body mass index, an indicator of the severity of
obesity.  The data collected between 2002 and 2006 also provided information on
diagnosis of kidney stone disease.
For the study. the researchers defined obesity as having a BMI of greater than
30 kg/m2 and calculated the incidence of kidney stones in people who were
non-obese and in those who were obese.
Among the non-obese study subjects, 2.6 percent were diagnosed with kidney
stones compared to 4.9 percent of the obese individuals, the study found.
Comparing those with mild obesity to those with severe obesity, the researchers
did not see any difference in the effect of obesity on the risk of kidney stone
disease.
The study itself does not reveal whether the association is a causal relation
meaning obesity may not necessarily be the direct cause for the high risk of
kidney stone even though the possibility can't be excluded.
By David Liu